CARTAGENA, Colombia - The subjects might not have been to Stephen Harper or Barack Obama's taste, but the exclusion of Cuba and the war on drugs dominated the discussion among hemispheric leaders at the opening of the Summit of the Americas.

The summit host, Colombian President Juan Manuel Santos, delivered a frank speech to the gathering in which he declared it would be "unacceptable" to hold another summit without Cuba present.

Cuba's membership in the Organization of American States (OAS) was suspended in 1962, and only Canada and the United States have not lobbied for it to be included at the summit table.

"The isolation, the embargo, the indifference, the looking the other way, don't work," Santos said. "This path is no longer acceptable in today's world. It's an anachronism that keeps us anchored in a Cold-War era that was overcome decades ago."

Similarly, the secretary general of the OAS made pointed remarks about promoting tolerance and dialogue.

"Democracy is advancing in the Americas and the best way to strengthen it is not with external pressure, impositions or exclusion," said Jose Maria Insulza.

Santos also said that the time had come to set aside "dogmas" of the past, and open a candid discussion about the war on drugs. He and many other Latin American leaders are calling for an analysis of the current policy of prohibition versus possible regulation and decriminalization.

The region, particularly Central America and Mexico, have suffered the loss of tens of thousands of lives in drug-related violence.

Harper's office has said the prime minister is not entertaining any change that would lift the prohibition of illicit drugs.

Latin America's increasingly united and emboldened voice comes at a time of impressive economic growth in the face of a global economic downturn. A new grouping of leaders, the Community of Latin American and Caribbean States (CELAC), includes all of the hemisphere's countries except Canada and the United States. The word "equality" came up often as leaders talked about relations in the region.

"One thing is for sure — the South is not longer the same and neither is Latin America and the Caribbean," said Alicia Barcena, the UN executive secretary of the Economic Commission for Latin America and the Caribbean.

And that's where Harper comes in.

Harper is spending the summit selling Canada as an attractive location for business and investment, and trying to encourage more trade — particularly with booming South America. Brazil is now the world's sixth largest economy.

Meanwhile, the Canadian manufacturing sector is suffering the effects of flagging exports as the U.S. and European economies continue to falter.

Harper told a forum of CEOs from the region about his Conservative government's budget promise to speed up the regulatory process for major natural resource projects.

"We cannot allow valid concerns about environmental protection to be used as an excuse to trap worthwhile projects in reviews-without-end. So, let me be clear: when it comes to evaluating development plans, one should not confuse the length of the process with the rigour of the science," Harper said.

"What matters is that the relevant facts are fully considered. That need not take years."

Harper also emphasized the Conservative government's cutting of corporate taxes.

"Our reliable, low-tax regime encourages the long-term investment that produces high-paying, highly-skilled jobs in the mining sector," Harper said.

"Our government understands that low, predictable taxes encourage business to do business. It is as simple as that."

Barcena of the UN suggested some areas where Canada and the southern part of the hemisphere could find common goals — in building new infrastructure to help transport goods, such as more highways linking countries to the Pacific, or in connecting more people to electricity and Internet grids.

Harper announced Saturday morning funding for a handful of initiatives in the Americas. A new "sustainable energy access" project would devote $9.55 million over six years to improve energy planning, regulation and corporate social responsibility across the region.

The Canada-Americas Business Environment Reform would provide $11 million-worth of technical assistance over five years to strengthen the investment climate in Latin America.

The government will also renew its commitment to the Organization of American States with $20 million over three years.

The official business of the summit had to compete for media attention with a scandal involving prostitutes and U.S. Secret Service agents. The scandal widened Saturday when the American military confirmed five service members staying at the same hotel in Colombia may have been involved in misconduct as well.

The Secret Service sent home about a dozen Secret Service agents for misconduct that occurred at their hotel before Obama's arrival in Colombia on Friday while military officials said five service members assigned to support the Secret Service violated their curfew and may have been involved in inappropriate conduct. Eleven secret service agents were placed on administrative leave, U.S. officials said Saturday.

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